To keep little feet—or big ones—from beating a dusty trail into your grass, install a few "stepping stones" made from composite decking. They're durable, rot-resistant, and affordable (or even free, if you use leftover boards). And the playful, cheery design will put a spring in your step for seasons to come.
The How-to: Place seven boards side by side, leaving ¼ inch between them for drainage, and trace a circle onto them. Use deck screws to attach a base of three boards perpendicular to the others, one at the centerline, the other two near opposite ends of the circle. Use a jigsaw to cut out the circle, then bury the base so that the piece is flush with grade.